/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.geode.internal;

import java.io.DataInput;
import java.io.DataOutput;

import org.apache.geode.DataSerializable;

/**
 * An extension to {@link DataOutput}, {@link DataInput} used internally in
 * product to indicate that the input/output stream is attached to a GemFire
 * peer having a different version.
 * 
 * Internal product classes that implement {@link DataSerializableFixedID} and
 * {@link DataSerializable} and change serialization format must check this on
 * DataInput/DataOutput (see
 * {@link InternalDataSerializer#getVersionForDataStream} methods) and deal with
 * serialization with previous {@link Version}s appropriately.
 * 
 * @since GemFire 7.1
 */
public interface VersionedDataStream {

  /**
   * If the remote peer to which this input/output is connected has a lower
   * version that this member, then this returns the {@link Version} of the peer
   * else null. If the peer has a higher {@link Version}, then this member
   * cannot do any adjustment to serialization and its the remote peer's
   * responsibility to adjust the serialization/deserialization according to
   * this peer.
   */
  public Version getVersion();
}
